Get obj export settings (properties) from ExportOBJ class shown in the UI in python script
Window manager methods

Prior to running python console code below I have exported the  scene to wavefront obj, set a filepath and chosen use selection.

&gt;&gt;&gt; wm = C.window_manager

&gt;&gt;&gt; props = wm.operator_properties_last("export_scene.obj")


Running auto-complete props.CtrlSpace

&gt;&gt;&gt; props.
          as_pointer(

          ... cut for brevity...


          use_normals
          use_nurbs
          use_selection
          use_smooth_groups
          use_smooth_groups_bitflags
          use_triangles
          use_uvs
          use_vertex_groups
          values(
&gt;&gt;&gt; props.


Can get any property value

&gt;&gt;&gt; props.use_uvs
True


This is the default value for use_uvs

If however we iterate over items, will get those values last used that are non default.

&gt;&gt;&gt; for k, v in props.items():
...     k, v
...     
('filepath', '/home/batfinger/Desktop/untitled.obj')
('use_selection', 1)


To run the operator again using the same properties from code could simply make this a dictionary and pass it to the operator as kwargs

&gt;&gt;&gt; d = {k : v for k, v in props.items()} # or d = dict(props.items())
&gt;&gt;&gt; bpy.ops.export_scene.obj(**d)
Progress:   0.00%
    (  0.0003 sec |   0.0000 sec) OBJ Export path: '/home/batfinger/Desktop/untitled.obj'
Progress:   0.00%
Progress:   8.33%
Progress:  16.67%
Progress:  25.00%
Progress:  33.33%
Progress:  41.67%
Progress:  50.00%
          (  0.0044 sec |   0.0034 sec) Finished writing geometry of 'Cube'.
Progress:  50.00%
Progress:  50.00%
Progress:  50.00%
      (  0.0058 sec |   0.0051 sec) Finished exporting geometry, now exporting materials
Progress: 100.00%
NO NODES!
      (  0.0074 sec |   0.0067 sec) OBJ Export Finished
Progress: 100.00%
Progress: 100.00%
Progress: 100.00%
Progress: 100.00%

{'FINISHED'}